diff --git a/packages/js/email-editor/src/hooks/use-preview-templates.ts b/packages/js/email-editor/src/hooks/use-preview-templates.ts
index 3420e7b47f..062699dba5 100644
--- a/packages/js/email-editor/src/hooks/use-preview-templates.ts
+++ b/packages/js/email-editor/src/hooks/use-preview-templates.ts
@@ -5,7 +5,6 @@ import { useMemo } from '@wordpress/element';
 import { parse } from '@wordpress/blocks';
 import { BlockInstance } from '@wordpress/blocks/index';
 import { useSelect } from '@wordpress/data';
-import { store as blockEditorStore } from '@wordpress/block-editor';
 
 /**
  * Internal dependencies
@@ -17,6 +16,10 @@ import {
 	EmailEditorPostType,
 } from '../store';
 
+// Shared reference to an empty array for cases where it is important to avoid
+// returning a new array reference on every invocation
+const EMPTY_ARRAY = [];
+
 /**
  * We need to merge pattern blocks and template blocks for BlockPreview component.
  * @param templateBlocks - Parsed template blocks
@@ -96,21 +99,12 @@ export function usePreviewTemplates(
 ): [ TemplatePreview[], TemplatePreview[], boolean ] {
 	const { templates, patterns, emailPosts, hasEmailPosts } = useSelect(
 		( select ) => {
-			const contentBlockId =
-				// @ts-expect-error getBlocksByName is not defined in types
-				select( blockEditorStore ).getBlocksByName(
-					'core/post-content'
-				)?.[ 0 ];
-
 			const rawEmailPosts = select( storeName ).getSentEmailEditorPosts();
+
 			return {
 				templates: select( storeName ).getEmailTemplates(),
 				patterns:
-					// @ts-expect-error getPatternsByBlockTypes is not defined in types
-					select( blockEditorStore ).getPatternsByBlockTypes(
-						[ 'core/post-content' ],
-						contentBlockId
-					),
+					select( storeName ).getBlockPatternsForEmailTemplate(),
 				emailPosts: rawEmailPosts,
 				hasEmailPosts: !! ( rawEmailPosts && rawEmailPosts?.length ),
 			};
@@ -128,15 +122,11 @@ export function usePreviewTemplates(
 		if ( parsedCustomEmailContent ) {
 			contentPatterns = [ { blocks: parsedCustomEmailContent } ];
 		} else {
-			contentPatterns = patterns.filter(
-				( pattern ) =>
-					// eslint-disable-next-line @typescript-eslint/no-unsafe-return
-					pattern?.templateTypes?.includes( 'email-template' )
-			);
+			contentPatterns = patterns;
 		}
 
 		if ( ! contentPatterns || ! templates ) {
-			return [];
+			return EMPTY_ARRAY;
 		}
 
 		const templateToPreview = [];
@@ -208,5 +198,9 @@ export function usePreviewTemplates(
 		} ) as unknown as TemplatePreview[];
 	}, [ emailPosts, allTemplates ] );
 
-	return [ allTemplates || [], allEmailPosts || [], hasEmailPosts ];
+	return [
+		allTemplates || EMPTY_ARRAY,
+		allEmailPosts || EMPTY_ARRAY,
+		hasEmailPosts,
+	];
 }
diff --git a/packages/js/email-editor/src/store/selectors.ts b/packages/js/email-editor/src/store/selectors.ts
index ca879bc08a..8abf73e7f0 100644
--- a/packages/js/email-editor/src/store/selectors.ts
+++ b/packages/js/email-editor/src/store/selectors.ts
@@ -1,12 +1,12 @@
 /**
  * External dependencies
  */
-import { createRegistrySelector } from '@wordpress/data';
+import { createRegistrySelector, createSelector } from '@wordpress/data';
 import { store as coreDataStore } from '@wordpress/core-data';
 import { store as interfaceStore } from '@wordpress/interface';
 import { store as editorStore } from '@wordpress/editor';
 import { store as preferencesStore } from '@wordpress/preferences';
-import { serialize } from '@wordpress/blocks';
+import { serialize, parse } from '@wordpress/blocks';
 import { BlockInstance } from '@wordpress/blocks/index';
 import { Post } from '@wordpress/core-data/build-types/entity-types/post';
 
@@ -29,6 +29,21 @@ function getContentFromEntity( entity ): string {
 	return '';
 }
 
+const patternsWithParsedBlocks = new WeakMap();
+function enhancePatternWithParsedBlocks( pattern ) {
+	let enhancedPattern = patternsWithParsedBlocks.get( pattern );
+	if ( ! enhancedPattern ) {
+		enhancedPattern = {
+			...pattern,
+			get blocks() {
+				return parse( pattern.content );
+			},
+		};
+		patternsWithParsedBlocks.set( pattern, enhancedPattern );
+	}
+	return enhancedPattern;
+}
+
 export const isFeatureActive = createRegistrySelector(
 	( select ) =>
 		( _, feature: Feature ): boolean =>
@@ -164,6 +179,22 @@ export const getSentEmailEditorPosts = createRegistrySelector(
 			) || []
 );
 
+export const getBlockPatternsForEmailTemplate = createRegistrySelector(
+	( select ) =>
+		createSelector(
+			() =>
+				select( coreDataStore )
+					.getBlockPatterns()
+					.filter(
+						( { templateTypes } ) =>
+							Array.isArray( templateTypes ) &&
+							templateTypes.includes( 'email-template' )
+					)
+					.map( enhancePatternWithParsedBlocks ),
+			() => [ select( coreDataStore ).getBlockPatterns() ]
+		)
+);
+
 /**
  * COPIED FROM https://github.com/WordPress/gutenberg/blob/9c6d4fe59763b188d27ad937c2f0daa39e4d9341/packages/edit-post/src/store/selectors.js
  * Retrieves the template of the currently edited post.